Electrical Engineering - Inductors - Discussion

@All.

I'm guessing that the frequency here is infinite because it's an instantaneous change, giving you a theoretically infinite resistance in the inductor (2*π*f*L), so approximately all of the voltage drop is in the inductor at t=0.

To break it down, a non-changing voltage level (constant DC voltage) has a frequency of 0, while an instantaneously changing voltage (such as a sudden flick of a switch) results to an infinite frequency (or extremely high frequency).

Then with impedances, we can infer that inductors resist high frequencies based on the formula while capacitors resist low frequencies more.

So, theoretically infinite frequency, with an inductor component in series, would result in a formula for the voltage drop of

V(inductor)=V(source)*2*π*frequency*inductance/(2*π*frequency*inductance+resistance)

With the voltage drop in the resistance to virtually zero.

Here Voltage does not change.

R=1000ohm,
V=6V,
Then, I= V/R=6/1000=0.006A.

And again R will not change because switch is off means R does not equal to zero,
Hence R=1000 ohm.

Then V =I * R = 0.006 * 1000,
= 6V.

IN SERIES RL CIRCUIT Vs=VL x (e^-t/time constant).

If t=0 ; Vs= VL x e^0.

Therefore Vs=VL = 6V in t=0.

As inductor doesnt allows sudden change in current. The voltage drop will be the same 6V.

At instant, there is no change in current of inducter, so the current will for some time .

V=IR
I=6/1=6 mA

After switch off current will remain same so the voltage will be
v=6*1=6 V.

As according to AC formula, V=Vm(1-e^-rt\L) for RL circuit the value of voltage at inductor will be zero, for the instant when switch is closed dc will behave same as AC.

The Answer is 6v as there is no back EMF produced by the current in the inductor when we just close the switch.

At t=0s ; f is infinite , and XL = 2pfL, hence XL is infinite.

Means open circuit.
Hence, the total voltage will be across an inductor and hence 6v.

Here we know from transient analysis that when switch is on (t=0) then initially inductor behave like a open circuit. So no current flow through the circuit because of open circuit therefore no we drop across are and input we appear across L.

Under transient condition (Here:-closing of switch) inductor behaves like open circuit so voltage across inductor is 6.

After than current in the circuit gradually increase and after finite time inductor behaves short circuit so that voltage across it 0.